[ML] Removing deprecated post data function (#199344)

`POST _ml/anomaly_detectors/<job_id>/_data` is being removed from es, it
can be removed from kibana too as it is unused.

https://www.elastic.co/guide/en/elasticsearch/reference/8.15/ml-post-data.html

x-pack/plugins/ml/server/lib/ml_client/ml_client.ts

@@ -615,10 +615,6 @@ export function getMlClient(
         p
       );
     },
-    async postData(...p: Parameters<MlClient['postData']>) {
-      await jobIdsCheck('anomaly-detector', p);
-      return mlClient.postData(...p);
-    },
     async previewDatafeed(...p: Parameters<MlClient['previewDatafeed']>) {
       await datafeedIdsCheck(p);
       return mlClient.previewDatafeed(...p);

x-pack/plugins/ml/server/lib/ml_client/types.ts

@@ -101,7 +101,6 @@ export type MlClientParams =
   | Parameters<MlClient['info']>
   | Parameters<MlClient['openJob']>
   | Parameters<MlClient['postCalendarEvents']>
-  | Parameters<MlClient['postData']>
   | Parameters<MlClient['previewDatafeed']>
   | Parameters<MlClient['putCalendar']>
   | Parameters<MlClient['putCalendarJob']>